It is illegal to let a dog ‘be dangerously out of control anywhere’, and dogs are considered dangerously out of control if they injury somebody or make someone worried they may injure them.

Allowing a dog to injury someone is punishable by up to five years in prison and an unlimited fine, while the dog could be seized and destroyed.

Last year, new powers to protect people against dog attacks were introduced, which allowed police and local authorities to demand owners take action or risk fines of up to £20,000.

If a complaint is made, officers can now order owners to attend dog training classes, muzzle their pet or keep it on a lead in public, require the dog to be micro chipped and to repair fencing to stop dogs getting out of gardens.

A police spokesman said: “This is a serious incident which has left somebody with a nasty injury.”